The Program will continue to function as a regional interdisciplinary center for collaborative studies on the development, molecular organization and function of contractile and regulatory proteins and on the mechanics, energetics, excitation-contraction coupling mechanism and intracellular ion movements in cardiac, smooth and skeletal muscle. Studies on cardiac and vascular smoothe muscle will be directed to determine the pathophysiological changes in these tissues in cardiovascular disease. Cryoultramicrotomy, intermediate high voltage electron microscopy and fluorescent antibody probes will be used to determine the state and organization of actin, myosin and regulatory proteins in cardiac, skeletal and vascular smooth muscle, platelets and leucocytes. Cardiac, smooth and skeletal muscle morphogenesis and its relation to injury and cardiac and blood vessel function will be studied. Smooth muscle mechanics and energetics will be correlated with fluorometric and nuclear magnetic resonance methods, and related to the ultrastructure of smooth muscle. The three dimensional arrangement of the T-tubule-sarcoplasmic reticulum system will be determined with high voltage electronmicroscopy. Electron probe analysis, electron energy loss analysis and freeze fracture will be used for the study of excitation-contraction coupling, and rapid and sensitive spectrophotometric techniques will be correlated with advanced electronoptical methods for the direct measurement of transmembrane and subcellular ion translocations.